Should I have my air ducts cleaned?

According to the the National Air Duct Cleaners Association (NADCA)  http://www.nadca.com:

“Heating, ventilation, and air conditioning (HVAC) systems have been shown to collection a variety of contaminants such as mold, fungi, bacteria and very small particles of dust that have the potential to affect overall health, The removal of such contaminants from the HVAC system and home should be considered one component in an overall plan to improve indoor air quality.

The best way to determine if the HVAC system cleaning was effective is to perform a visual inspection of the system before and after cleaning. If any dust or debris can be seen during the visual inspection, the system should not be considered cleaned. While you can perform your own visual inspection using a flashlight and mirror, a professional cleaning contractor should be able to allow you better access to system components and perhaps the use of specialized inspection tools. In addition, following the Residential Cleaning Checklist can help to ensure a top quality job.

Frequency of cleaning depends on several factors, not the least of which is the preference of the homeowner. Some of the things that may lead a homeowner to consider more frequent cleaning include:

• smokers in the household
• pets that shed high amounts of hair and dander”